Reduction of spectral phonon relaxation times from suspended to supported graphene

Bo Qiu, Purdue University
Xiulin Ruan, Birck Nanotechnology Center, Purdue University

Date of this Version



Bo Qiu and Xiulin Ruan. Appl. Phys. Lett. 100, 193101 (2012);


Copyright (2012) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Appl. Phys. Lett. 100, 193101 (2012) and may be found at The following article has been submitted to/accepted by Applied Physics Letters. Copyright 2012 Bo Qiu and Xiulin Ruan. This article is distributed under a Creative Commons Attribution 3.0 Unported License.


We have performed molecular dynamics simulations with phonon spectral analysis to predict the mode-wise phonon relaxation times (RT) of suspended and supported graphene at room temperature, and the findings are consistent with recent optical measurements. For acoustic phonons, RTs reduce from up to 50 ps to less than 5 ps when graphene is put on silicon dioxide substrate. Similarly, optical phonon RTs reduce by half when supported. Stronger interfacial bonding is found to result in more RT reduction. Our results provide a fundamental understanding at the spectral phonon property level for the observed thermal conductivity reduction in supported graphene. (C) 2012 American Institute of Physics. []


Nanoscience and Nanotechnology